Controlling means for machines



March 8, 1927.

M. H. BALLARD CONTROLLING MEANS FOR MACHINES 4 Sheets-Sheet 1 Filed NOV.15. 1920 March 1927.

' 1,620,001 M. H. BALLARD CONTROLLiNG-MEANS FOR MACHINES Filed Nov. 15.1920 4 She ts-Sheet 2 //v VE/V 777/1 March 8, 1927. 1,620,001.

M. H. BALLARD CONTROLLING MEANS FOR MACHINES Filed Nov. l5, 1920 4Sheets-Sheet 5 arch 7 M. H. BALLARD CONTROL-LYING MEANS FOR MACHINESFiled Nov. 15. 1920 law Patented Mar. 8, 1927,

UNHTED STATES PATENT QFFICE.

MILTON H. BALLARD, OF LYNN, MASSACHUSETTS, A$SIGNOR TO UNITED SHOE MA.-

GHINERY CORPORATION, OF PATERSON, NEVT JERSEY, A CORPORATION OF NEWSerial No. 424,223.

JERSEY.

CONTROLLING MEANS FOR MACHINES.

Application filed November 15, 1920.

This invention relates to controlling means for machines and moreparticular iv to such means as will serve as safety devices inconnection with starting and stopping mechanisms of machines.

In certain classes of machines it is of more than ordinary importancethat accidental repetition of the actuation of work operating parts beprevented. Typical examples of machines in respect to which suchrepetition is especially undesirable, are furnished by beam presses ofthe type disclosed in United States Letters Patent No. 368,108, grantedAug. 9, 1887. on application of Henry Parsons, and designed for cuttingleather or other materials, Such a machine comprises characteristicallya cutting block and a relatively heavy beam which is moved toward theblock during cutting operations to apply pressure by which dies, areforced through work resting on the block, after which the beams israised to its uppermostposition of rest to permit of the propermanipulation of the Work and of the die preliminary to a succeedingcutting operation.

It will be. apparent that in a construction where a heavy beam or otherdriven part is raised to a high point at its position of rest thatexcessive overthrow of the driving shaft, that is rotation of the shaftvery far at least beyond the point that marks the termination of normalrotation. would be likely to bring the beam down again in a repetitionof the pressure applying operation, with the possibility of disaster tothe work and to the operator. This undesirable overthrow may be theresult of defective braking caused by excessive wear on the frictionalsurfaces of the cooperating brake part which are subject 'to severestrains in heavy machines; or because of the loosening or the fractureof the brake due to accidental overloading of the machine; or due toseizing of the shaft by the power pulley, caused commonly bydeficiencies or defects in lubrication.

Another cause of such repetition is that, through carelessness of theoperator or because of inadequate or defective operating parts, thestarting devices remain in position to initiate a recurrence of thecycle of operations, when the driving means is overthrown, due to any ofthe causes above enumerated.

Still another common defect in machines having heavy driven members isthat, during such times as the brake is inoperative, the membersoccasionally back down, accompanied by rotation of driving means in adirection reverse of normal, due to the failure of the driving mechanismto lift the members to the normal position of rest, thus resulting in anundesired and possibly dangerous actuation of the work operating parts.

In View of the foregoing, it is an object of this invention to providemechanism especially simple and durable in construction and efficient inoperation for controlling the power means in machines, and forpreventing disadvantageous or dangerous operation of the driven parts.It is to be understood, however, that-Vin its various aspects the 'invention is not limited to embodiment in a beam press of the typereferred to.

In one aspect the invention resides in improved means for preventingoperation of the starting devices of a machine when a driving elementhas failed to stop at the proper point in the preceding cycle ofoperations. Conveniently, the means comprises a latch mounted to rotatewith the driving element and operative in any such case to lock thestarting means against manual operation.

In another aspect the invention contemplates improved means forpositively looking the driving means against rotation beyond apredetermined, amount over normal rotation, thus preventing a repetitionof the cycle of operations of the machine. In the illustrativeconstruction, the said means comprises a relatively heavy lock mountedon a firm, stationary support and operative to prevent rotation of theshaft beyond a predetermined point.

- Heretofore in those cases in which the pulleyhas seized the shaft, ithas required considerable Work by an expert mechanic in order tocondition the machine for operation, and an important object of thisinvention is to provide a construction by whlch the ordinary workman canreadily make repairs when the connections between the pulley and theshaft have become damaged through lack of care or because of defectivelubrication. In the illustrative construction an improved bearing isprovided for the pulley comprising preferably two concentric sleeves orhearings. the inner of which is releasably attached to the shaft and theouter to the pulley by a frangible pin or stud.

The invention contemplates also an improved means for preventing reverserotation of the driving means which drives the work operating parts ofthe machine. As indicated in the foregoing discussion such a means isespecially applicable to machines which comprise heavy driven parts. Inthe illustrative construction the shaft of such a machine is providedwith a segmental rack fixedly secured thereto and adapted to beengagedby a pawl controllable by a clutch or friction ring on saidshaft. the construction and arrangement being such that the pawl whichis secured to a firm. stationary support will engage with the rackshould the shaft start to rotate in a direction reverse from the normaland lock said shaft positively against movement in said direction. thuspreventing the beam from backing downwardly.

As a further means for ensuring proper operation of the starting andstopping mechanisms. the prime starting member is returned to operativeposition in a positive manner to effect the withdrawal of a clutchcontrolling or operating member at the termination of a predeterminednumber of revolutions of the power pulley. In the illustratedconstruction. the prime starting member also controls the setting of thebrake whereby proper operation of the latter is member. which fitsinside of the pulley, and

associated parts;

Fin. 5 1s a view in side elevation of the illustrated mechanism of Fig.1:

Fig. 8 is a view in side elevation of the mechanism shown in Fig. 7.

Fig. 9 is a detail of the brake operating means.

In the illustrative mechanism a power pulley 10' is mounted for freerotation on the shaft 12, there being interposed between the pulley andshaft two concentric bushings 14 and 16 respectively (Fig. of which theinner bushing 16 is releasably connected to the shaft 12 preferably bymeans which will be hereinafter described. As shown, the bushing 16 isprovided with perforations 18 which act as reservoirs for a lubricant,passageways extending from the pockets 18 to grooves 19 in the outersurface of the hearing 14 to which the lubricant is carried through theoperation, in part at least, of

centrifugal force. thus ensuring that with ordinary care the surfacesbetween the pulley, the bushings and the shaft will be well lubricatedso that the pulley will turn without friction under normalconditions.The bushing 16 is provided with a flange 22 preferably integraltherewith and having a socket at the outer end of the passage 24. (Fig.3) adapted to receive the conical end of the plunger 26 mounted slidablyin the clutch block 28 which is lined to the shaft 12. By this means thebushing 16 is releasably connected to the shaft to move therewith underordinary conditions. Normally the pulley turns on the outer surface ofhushing 16 and, if for any reason friction should develop between theouter bearing surface of bushing 16 and the inner contacting surface ofthe bushing 1% so that said bushings ad here to each other, the plunger26 will be retracted. releasing the bushing 16 from the clutch block,then the pulley 10, together with the bushings 14 and 16 will turn,through a small are, on the bearing surface provided by the shaftitselfuntil the bush ing 16 is locked against movement by a hook 21 secured tothe flange 22 of the bushing. as will be hereinafter described. Shouldthis condition go unnoticed by the operator of the machine. friction maydevelop to such an extent that the bearing surfaces between bushings 1 1and 16 will adhere to each other or, in other words. the pulley with itsbushing 1% to which it is secured by a frangible pin 20, will seize thebushing 16 and in such case provision is made for the release of thepulley from the outer bushing 14 through the shearing of the pin 20,thus permitting the pulley to turn on another surface. namely thatbetween the pull ev and the outer surface of the bushing 14. It will beclear from the description of the pulley and its concentric hearingsthat there is provided a construction which is well adapted to meet amost unusual set of conditions all tending to damage or completelydestroy the operative connection between the pulley and the bearing 14.

the shaft. It will be understood that normally the pulley rotates freelyon the outer surface of the bearing 16. Should conditions'arise makingthis mode of operation impossible, the pulley will next turn with itsbearing directly onthe exterior surface of Long before this occurs, thecondition of the machine should be discovered by the operator who maythen readily replace the worn or damaged parts.

For holding the pulley with its attached bushing 14 in proper positionon the shaft 12, that is, in coutact with the clutch member 28, there isprovided a nut 32 screwed on the shaft 12 and having interposed betweenitself and the pulley a fiber and a metal washer 34 and 36 respectively.

As before stated, the pulley is mounted to rotate loosely with respectto the shaft 12,

means in the form of clutch mechanism being provided for operativelyconnecting the pulley to the shaft so that the rotary motion of thepulley is communicated to the latter. In the construction shown, theclutch is pref crably, although not necessarily, of the one revolutionnon-repeating type shown in the Patent No. 1,011,903. granted December19, 1911, on an application filed by Arthur Bates. Located in a circularchamber in the pulley 10 is an annular clutch member or split ring 38,the two lower ends of the splitportions being united by a dowel pin 40(Fig 1) while the upper ends of the ring portions are spaced toaccommodate a clutch ring e1:- panding device comprising a togglemechanism shown in detail in Figs. 1 and 4. For supporting the ends ofthe toggle link members 42. there is provided in each of the spaced endsof the split ring 88 a block 44 having a seat or cup to receive the endof the toggle link, the other end of which is received in acorresponding seat or cup in a block 46 which is freely slidable to alimited extent in a plunger 48 which is supported in the clutch member28 for endwise sliding movement and which has its free end projectinginto the space between the split ring members 38. As shown. the plunger48 has a chamber extending approximately half of its length for housinga spring 50. one end of which rests against a plate 52 fixed to theclutch member 28 and whiclris operative to urge the plunger in adirection to straighten the toggle link members 42 and thus apply theannular clutch member 88 to the inside of the pulley 10 in a clutchingoperation. For retracting; the plunger 48 the latter is provided with anextension 54 having a shoutder adapted to be engaged by a wedge member56 carried by the lever 58 pivoted at ($0 on a fixed support such as acircular plate (52 which is fixedly bolted by bolts 64 to the frame 66(Fig. 5) ofthe machine. It will be understood that the wedge member orcam 56'engages the projection 54 on the plunger 48 and positivelyretracts the plunger to break the toggle and thus release the clutchring 38 from the pulley 10. It should be stated that the clutch ring 38is operatively connected to the clutch member 28 through a rigid arm 68extending from the latter and which is located in a pocket formedbetween the lower ends of the split ring members 88, the constructionand arrangement being such that the clutch ring 38 is retainedpositively in a fixed relation with respect to the clutch member 28which, as before stated, is keyed to the shaft 12. Hence when throughthe operation of the plunger 48, the clutch ring 38 is frictionallyengaged with the inner surface of the pulley 10, the said pulley isclutched to turn with the clutch member 28 and with the shaft 12. Whilethe spring 50 can be depended upon to exert force suflicient tostraighten the toggle because adjustment of the toggle mechanism isprovided for to that end as will be hereinafter described, it isdesirable to provide positive means for moving the plunger in thedirection to straighten the toggle mechanism and, in the constructionshown, a stationary cam 70 is provided on a stationary support such asthe fixed plate 62 for contacting with the end face of the projection 54on the plunger 48 and operative to ensure the movement of the plungertoward the right in Figure 8. It will be understood that the lever 58 isconnected by link 71 to manually operable means as will be hereinafterdescribed by which the wedge or cam 56 on the end of the lever 58 islifted out of engagement with the projection 54 on the plunger 48 sothat the spring 50 is permitted to move the plunger in a direction toapply the clutch ring by straightening of the toggle links 42. After thewedge has thus been lifted out of contact with the projection 54 on theplunger 48, it is allowed to drop back again in prior constructions soas to be in position to retract the plunger 48 at the end of onerevolution of the shaft. In the present construction, however, the lever58 is provided with a block 7 2 on the side thereof and opposite thewedge or cam 56 in a position to be engaged by a cam surface on theinner surface of a flange 74 on the fixed clutch block 28, the camsurface operating positively to draw the operative end of the lever 58into position to retract the plunger 48 at the end of one revolution ofthe shaft. It will be understood that while the cam flange 74 positivelyreturns the lever 58 to operative position, it does not maintain it insuch position to the end of the revolution, the spring 179, hereinafterdescribed, being depended upon to accomplish this result. Thus when theparts come to rest, the cam flange 74 is spaced from the block 7 2 adistance sulficient to permit the lever 58 to be lifted to free theplunger 48 to start the machine in operation. Upon retraction of theplunger, the clutch ring members 38 more out of contact with most of theclutch surface on the pulley, this movement being due largelyto theaction of spring T5.

Referring to the adjustment for the toggle comprising toggle links 42,it will be observed that the block 46 is in fact. made up of two partsseparated by a wedge 7 8 adapted to be adjusted by a set screw 80 whichmay be screwed down to engage the head of the wedge and force it to theright in Figure 4,, thereby making the toggle structure substantiallylonger whereby greater pressure is applied to the ends of the split ringclutch 38 upon straightening the toggle. This adjustment of the toggleshould be such that the spring can just straighten the toggle when thespring is released for ac-' tion. For moving the wedge 78 in theopposite direction there is provided a washer 82 which is constantlypressed against the point of the wedge by a spring 84 in a socket in theplunger 48, the arrangement being such that the spring-pressed washerassists in adjusting the wedge 78. In passing it may be noted that theend of the plunger 48 is split laterall as at 86 and a set screw 88passed therethrough to draw the spaced end of the plunger toward thebody portion thereof and thus clamp the set screw 80 in its adjustedposition. The great advantage of a toggle mechanism in the relationdescribed resides in the fact that as thespring lessens in expansiveforce progressively with its expansion the toggle becomes progressivelymore effective and compensates for the loss of power in the spring sothat a. spring and toggle mechanism is more eifective than a spring andscrew mechanism like that shown in certain prior constructions.

In connection with the clutch block 28 which is keyed to the shaft 12there is provided a braking means which is preferably in the form of abrake band 90 which embraces the circular surface of the block 28 andhas one of its ends fixedly secured to a stationary support such as ringplate 62 by means of a bolt 92 mounted in said plate. In order that thisend of the brake band may be held adjustably, it is attached to the saidbolt indirectly through a yoke member 94 carrying a bar 96 around whichthe end of the brake band is lapped and secured. the said yoke beingfurther provided with a screw threaded member 08 which has its endengaged rotatably in a circumferential groove in the said bolt so that,upon turning the member 08, the yoke is moved transversely of the bolt06, thus tightening or loosening the brake band. lr'leans is provided.for holding the other end of the brake band in such manner that the bandmay be loosened or tightened upon the brake surface of the block 28 atpredetermined times properly related to the time of setting or releasingthe clutch. In a preferred construction this latter means comprises alever 100 (Fig. 1) pivoted upon a bolt 102 mounted in a bearing 104extending from the stationary ring member 62. Carried by a laterallyoil'- set end of the lever 100 is a roll 106 held constantly in contactwith a cam surface 108 on the block 28 by means of a spring 110, theconstruction being such that the lever 100 is operated to tighten theband 90 and thus apply the brake at the time the clutch is released fromthe pulley 10, the object being to stop the shaft definitely at the endof one revolution of the latter. Carried on the bolt 102 is a bifurcatedmember 112 which has a forked portion to straddle the lever 100 andanother forked portion to support a pin 114 to which the end of thebrake band 90 is directly connected. Another arm of the member 112 isbifurcated and carries a pin 116 upon which is pivoted one end of eachof toggle link members 118, other link members 120 of the toggle beingpivoted to the lever 100. At the elbow 122 of the toggle there ispivoted a link 124 having its other end pivotally attached at 126 to anarm 128 fixed to a sleeve or casting 129 rotatable on a stationary rodor shaft 130. This same sleeve or casting 129 carries fixedly anotherarm 132 to the outer end of which is pivoted a rod 134 adapted to beconnected at its lower end to a treadle or other manually operable meansunder the control of the operator. The arrangement of this part of thebrake mechanism is such that upon operating the treadle, the rod 134 ispulled downwardly, thus forcing the link 124 to the left in Figure 1breaking the toggle and turning member 112 on its pivot to loosen thebrake band 90. Since this downward movement of the rod 134 isaccomplished by the same movement of the treadle which initiates theclutching of the pulley to the shaft, it is clear that the brake band isloosened prior to the rotation of the shaft and hence the machine startswithout the drag of the brake. Very shortly after the beginning of therotation of the shaft the roll 106 on lever 100 drops from the high part109 of the cam 108. thus further loosening the brake band. On the otherhand, when the treadle rod 134 is released the toggle. comprised oflinks 118 and 120, is immediately straightened through reverse rotationof the sleeve 129 by the power operated lever 58 and connecting link 71.Hence the brake band 90 is applied in full force when the roll 106 ridesup on the high part of the cam 108 which occurs practicallysimultaneously with the retraction of the plunger 48 and the release ofthe clutch ring 38 from the pulley 10.

In order that the rod 134 may be released from the treadle early in therotation of the shaft to permit of the return of the starting lever 58to operative position and of the straightening of the brake band toggle118 and 120 (which effects the conditioning of the brake band forimmediate application as above described), and for other reasons whichwill be hereinafter set forth, a detachable connection is providedbetween said rod and the treadle which, in the illustrative construction(Figs. 2 and 6), comprises an arm 1410 fixedly secured to the treadleshaft 142 and having a bifurcated end 14 1 which embraces the lower endof the rod 134 which is held within the forked extremity through theoperation of the spring 146 having its ends attached respectively to therod and the arm 140. Secured to the rod 134 at a point below the arm 140is an adjustable stop 1 18 having a slanting surface and a shoulder atits upper end, both for cooperation with a latch 150 pivoted at 152 uponthe arm 141-0 and held away from the arm in normal operative position bymeans of a spring 154 located in aligned sockets in the arm and in thelatch respectively. For disengaging the rod 134; from the latch 150against which it is held by spring 146 there is provided means which ispreferably automatically operative for the purpose, thus ensuring thatthe treadle rod 1.34 will be released at the proper time whether theoperator keeps the treadle depressed or not. Hence the mechanism is foolproof in this as in other respects as will be hereinafter pointed out.In the illustrative mechanism, the lever 158 (Fig. 1) pivoted at 160upon the stationary plate 62 is arranged to have its upper end contactedby the higher part 109 of the cam 108 on the block 28 by which it isforced outwardly, thus causing the lower end of the lever to move to theleft in Fig. 1, to swing the rod 13 1 in the same direction, that isoutwardly away from the latch 150 in Fig. 2 and to release the rod fromsaid latch and from the arm 140 on the treadle shaft. At the end of acycle of operations or when the treadle has been released by theoperator the arm 14-0 swings upwardly, thus carrying the latch 150 overthe slanting surface of the stop 14-78 and into engagement with theshoulder at the upper end of said stop, thus re-establishing operativeconnections between the treadle and the treadle rod 134. For the purposeof limiting the movement of the treadle there is provided an arm 153conveniently integral with the arm 14-0 and fixedly secured to thetreadle rod 1 1-2. Mounted in the free end of the arm 153 are twoadjustable members 155 adapted to contact with portions of the machineframe to set limits to the swinging movement of the treadle which is normally held yieldingly at its upper limit by means of a spring, notshown, in cooperation with the lower of the two members 155. It will beclear from an inspection of Figs. 2

and 6 that the upper member 155 restricts the downward movement of thetreadle. As soon as the treadle is released by the operator it is movedto its upper limit of rest so that the latch 150 may re-engage over thestop member 1 18 on the rod 134, thus connecting the treadle to thestarting mechanism of the machine.

In the illustrative construction, the means for checking or ratherabsolutely locking the snaft against rotating beyond a predeterminedpoint comprises a latch or looking member 16 1 fixedly attached to thesleeve or casting 129 rotatable on the rod or shaft 130 and having itsupper end arranged normally for co-operation with a shoulder 166orabutment' on the block 28. It will be observed that the rod or shaft130 is mounted fixedly in a strong stationary support such as thestationary ring plate 62 which, in turn, is fixedly bolted to the frame66 of the machine and that if considerable pressure comes upon the saidlock it is firmly resisted since the sleeve or casting 129 upon whichthe lock is,

mounted, is backed up by a bracket or extension 168 (Fig. 5) extendingbeyond the plate 62. it will be understood that the lock 16 1- since itis fastened to the casting 129 is withdrawn from operative position atthe same time that the clutch is thrownin and the brake released throughthe rotation of the casting by the treadle rod 134 and further that thelock 164 returns to operative position practically simultaneously withthe application of the brake band and hence if the brake should slip orbreak and the shaft for that or for any other reason should overthrow,the lock would be in place to prevent excess overthrow of the shaft andabsolutely lock it against such rotationas would cause operation of themachine in which the present mechanism is embodied. As before stated,means is provided for locking the starting mechanism against operationif the shaft has overthrown to a predetermined extent in the precedingoperation of the ma chine, due to seizure of the shaft by the pulley orto slipping or breaking of the brake. In the illustrative constructionthis means comprises a finger 170 also fastened to the casting or sleeve129 and having its upper end in position to be engaged by the hook 21carried by the bushing 16 attached to the sl'iaft 12. It will be clearfrom reference to 1 and 5, that with the hook-21 engaged over the upperend of the finger 170, it will be impossible for the operator to depressthe treadle rod 134 to startthe machine. In this way the operator isgiven warningthat some thing is wrong with the machine and which shouldreceive attention before proceeding with further operations.

It should be noted that the lock 164: and the finger 170 are positivelyreturned to ing positively controlled since the lever 58 is returnedthrough unyielding means to its operative position, the said meanscomprising the block 72 and the cam surface on the flange 7 4 as setforth in the foregoing description. To insure as far as possible thatthe lock and finger will be returned promptly to operative position atthe proper time, even should the lever 58 be broken,

there is provided a spring 179 having one of its ends fastened to thecasting or sleeve 129 and its other end to a stationary part in suchmanner as to tend constantly to rotate the sleeve in the properdirection. Should the starting lever or treadle be locked againstoperation, the operator can readily determine the cause by inspectingthe mechanism and particularly the relative positions of the lock 164and the shoulder 166 designed to co-operate therewith under certainconditions. If, for instance, the shoulder 166 is in contact with theupper end of the lock 16% then the brake'band has slipped or failed tooperate for this or for some other reason such as breakage of the bandor of its support. In abnormal conditions due to failure of the brakeband to function normally the shaft 12 overthrows and both wvith the endof the lock 16% then the condition is one in which the pulley with itsattached bushing 1e has seized upon the bushing 16 and carried it alonguntil the hook 21 carried by the last mentioned bushing engages with thefinger 170. As stated, when this occurs the starting means to which thefinger 170 is connected'is prevent-ed from being operated, the operatorfinds it impossible to depress the treadle to start the machine.Referring to Fig. 1 of the drawings, it will be clear that with the hook21 engaged over the upper end of the finger 17 0 the sleeve 129, whichfixedly carries the finger, cannot be rotated and hence the rod 134,which is connected thereto, cannot be moved downwardly, and thus thetreadle is held against the'pressure of the operators foot. It will beclear, therefore, that the construction and arrangement of the bushings14 and 16 is such as to cooperate with the starting means in warning theoperator of a deficiency or defect in the lubrication of the bearingsfor the bushings and for the pulley. The first result of insufiicientlubrication manifests itself by the locking of the finger 170 of thestarting means agalnst actuation, due to the engagement of the hook 21with the upper end of the said finger. It will be understood that withthis locking of the finger 170 there takes place simultaneously thelocking of the bearing 16 against rotation, since the hook 21 issecurely fastened to the flange 22 of the bearing 16. In this abnormalcondition of affairs the pulley 10 might rotate for a time on bushing 16until the friction on the bearing surface of bushing 16 became toogreat, and then it would rotate on the outer surface of the bearing 1%,this being I rendered possible through the shearing off of the pin 20.l/Vhen the operatorfinds it impossible to start his machine, aninvestigation should disclose the cause, which can be corrected withoutcalling in a skilled mechanic. All that it is necessary to do is toremove the pulley, introduce the proper amount of lubricant and returnthe pulley to position with the pin 26 engaged in the socket inthe'fiange 22 of the inner bushing. Other causes of overthrow of theshaft can usually be corrected by proper attention to the brake band orto the adjusting means therefor,

As stated in the foregoing discussion it is possible for the shaft torotate in a direction reverse to'normal under the weight of eX-ceptionally heavy work operating parts, such as a beam in a beam dinkingmachine. In the illustrative construction means is provided forpreventing such reverse. rotation of the shaft, the said means as showncomprising a segmental rack 180 fixedly secured to the shaft 12 which isconveniently the same shaft that carries the power pulley and the clutchmechanism. For co-operating with the rack 180 there is provided a pawl182 mounted upon or integral with a bar 184 which has its lower endpivotally secured to the frame of the machine or to the floor or to anyother stationary support. Normally the pawl is held out of engagementwith the teeth of the rack 180 and is moved into such engagement bymeans controlled by the shaft 12. Such means in the illustrativeconstruction comprises a friction clutch 186 which in its simplest formis a ring mounted in a circular block 188 fastened to the shaft 12 andconsisting of split portions or halves indicated at 190 which permitofthe ring being introduced into its seat or groove in the block 188 inpieces which are then secured together through the manipulation of thescrew members 192. The adjustment of the ring 186 is secured by frictionblocks 193 of wood or any other suitable material mounted in the plate195 of the block 188 and pressed by individual springs into contact withthe ring 186 so as to carry the ring along with the shaft in itsrotation in the direction of the arrow in Fig. 7 and to permit of thechecking of the movement of the ring through the link connection 194with the bar 184, the construction and arrangement being such that thebar 184 is carried to the right in said figure removing the pawl tooth182 from engagement with the segmental rack, it being understood thatoutward movement of the bar 184 away from the segment is limited by astop such as a bar or rod 196. On the other hand, rotation of the shaft12 in a direction reverse to that indicated by the arrow in Fig. 7 willpromptly draw the bar 184 toward the segment rack 180 through theconnecting link 194, the ring 186 to which the link is connected beingheld sufficiently tight in its seat by blocks 193 in the block 188 tocause such operation of the bar 184. It will be clear that movement ofthe bar 184 to the left in Fig. 7 causes the engagement of the pawl withone of the teeth of the segmental rack and instantly locks the shaftagainst further reverse rotation. Mounted upon the shaft 12 or upon theblock 188 in fixed relation thereto is a toothed wheel 200 which may been aged by any ordinary form of bar as a lever to turn the shaft 12 byhand in case such an operation becomes either necessary or desirable.

The normal operation of the above-described mechanism is as follows :Thetreadle shaft 142 is rotated, causing the arm 140 with the rod 134 tomove downwardly, turning the casting 129 in a clockwise direction, andthereby moving the locking members 164 and 170 into inoperativeposition. The link 124 breaks the toggle 122 to loosen the brake band90, and the link 71 operates to move the lever 58 outwardly, releasingplunger 48 which straightens the toggle members 42, thus connecting theclutch block 28 and shaft 12 with the rotating pulley 10 by means of thesplit ring 38. Shortly after the beginning of rotation of the shaft 12,the roll 106 drops from the high part 109 of the cam 108, furtherloosening the brake band. The cam then causes the lever 158 to move therod 134 to the left, disengaging the same from the latch 150 and arm140, permitting the return of locking element 164 and 170 and the toggle118, 120 to operative position. This return is initiated by the lever 58when it is moved inwardly upon engagement with the cam on the innersurface of flange 74 of the clutch block. At the end of one revoltion ofthe shaft the lever operates to cause a retraction of the plunger 48 todisengage the clutch from the pulley, and the roll .106 reaches the highpart of the cam 108 to effect the application of the full force of thebrake. The arm 140, when released by the operator, is returned by aspring to its initial operative position.

The operation of the parts of the mechanism under abnormal conditionshas a ready been pointed out and requires no further explanation.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent of the United States is 2- 1. In amechanism of the class described, a shaft, a power pulley, a clutch foroperatively connecting the pulley to the shaft, starting means forcontrolling the clutch, a brake operative normally to prevent furtherrotation of the shaft after the disconnection of the pulley from theshaft, means operating to lock the shaft against rotation whenever thebrake becomes inoperative, said locking means normally moving toinoperative position when the clutch is rendered operative, and a singlemeans for returning the starting means and the locking means tooperative position.

2. In a mechanism of the class described, a shaft, a power pulley, aclutch for operatively connecting the pulley to the shaft comprising amember keyed to the shaft, a

starting lever for controlling the clutch, a brake operative normally toprevent further rotation of the shaft after the disconnection of thepulley from the shaft, and a locking member arranged to co-operate withthe member keyed to the shaft to prevent rotation of the shaft in casethe brake should become inoperative, said locking member normally movingto inoperative position when the clutch is rendered operative, andinterconnected means normally operative for returning the starting leverand locking member to operative position.

3. In a mechanism of the class described, a shaft, a power pulley, aclutch for operatively connecting the pullev to the shaft comprising amember keyed to the shaft and having a shoulder, a starting lever forcontrolling the clutch, a brake operative normally to prevent furtherrotation of the shaft after the disconnect-ion of the pulley from theshaft, and a locking pawl for cooperation with the shoulder on saidkeyed member for locking the haft against excess rotation should thebrake become inoperative, said locking pawl normally moving toinoperative position when the clutch is rendered operative, and cammeans for positively moving both the starting lever and the locking pawlto operative position.

4. In a mechanism of the class described, a shaft, a power pulley,clutch means for operatively connecting the pulley to the shaftcomprising a member keyed to the shaft and having a shoulder, a brakeopera tive normally to prevent further rotation of the shaft after thedisconnection of the pulley from the shaft, a locking pawl forcooperation with the shoulder on said keyed member for locking the shaftagainst excess vent further rotation of the shaft after thedisconnection of the pulley from the shaft. a locking means forpreventing excess rotation of the shaft in case the brake should becomeinoperative, and connections from the starting means to the lockingmeans for ensuring the return of the locking means to operativeposition.

6. In a mechanism of the character described, a shaft, a. power pulley,clutch mechanism for operatively connecting the nulley to the shaft, abrake band operative normally to stop the rotation of the shaft afterdisconnect-ion of the clutch, starting means for controlling saidclutch, and means for locking the starting means against actuation incase of excessive overthrow of the shaft.

7. In a mechanism of the character de scribed, a shaft, a power pulley,clutch mechanism for 'operatively connecting the pulley to the shaft, abrake operative normally to stop the rotation of the shaft afterdisconnection of the clutch, starting means for controlling said clutch,and means for locking the starting means against actuation in case thebrake should become inoperative.

8. In a mechanism of the character described, a shaft, a power pulley,clutch mechanism for operatively connecting the pulley to the shaft, abrake operative normally to stop the rotation of the shaft afterdisconnection of the clutch, starting mechanism for controlling saidclutch, and means movable with the shaft for locking the startingmechanism against operation in case of excessive overthrow of the shaft.

9. In a mechanism of the character described, a shaft, a power pulley,clutch mechanism for operatively connecting the pulley to the shaft, abrake operative normally to stop the rotation of the shaft afterdisconnection of the clutch, manually operable starting mechanism forcontrolling said clutch comprising a projecting portion provided with ashoulder, and a hook member mounted on the shaft and operative to engageover said shoulder to prevent actuation of the starting means in case ofXcess movement of the shaft to a predetermined e: tent.

10. In a mechanism of the class described, a shaft, a pulley, a clutchfor operatively connecting the pulley tothe shaft, starting mechanismfor initiating the operation of the clutch and for releasing the clutchfrom the pulley, positively operated means for ensuring engagement ofthe clutch with the pulley, and positively operated means for ensuringreturn of the starting means to clutch releasing position.

11. In a mechanism of the class described, a shaft, a pulley, a clutchfor operatively connecting the pulley to the shaft, locking means forpreventing overthrow of the shaft and starting means for controlling theclutch both of said means being connected to a manually operable member,means operative to release the starting means and the looking means fromthe control of said manually operable member at a predetermined point inthe rotation of the shaft, and positively operatedmeans for returningboth the starting means and the locking means to operative position.

12. In a mechanism of the class described, a shaft, a pulley, a clutchfor operatively connecting the pulley to the shaft, starting means forinitiating operation of the clutch and for releasing the clutch fromoperative connection with the pulley comprising a member which ispositively moved to clutch releasing position. said starting meanscomprising a manually operable member, and means automatically operativeto disconnect the manually operable member from said positively movedmember.

13. In a mechanism of the class described, a shaft, a bushing releasablyattached to the shaft, a power pulley rotatable on the bushing, a clutchfor operatively connecting the pulley to the shaft, and means forlocking the shaft against excess rotation in case the pulley shouldseize the bushing.

14. In a mechanism of the class described, a shaft, a bushing on theshaft, a power pulley rotatable on the bushing, a clutch for operativelyconnecting the pulley to the shaft, starting means for controlling theoperation of the clutch, and means for looking the starting meansagainst manual operation in case the shaft should be carried beyond apredetermined point in its rotation by the pulley seizing the bushing.

15. In a mechanism, of the class described, a shaft, a bushingreleasably attached to the shaft, a pulley mounted for rotation on saidbushing and having a second bushing interposed between the pulley andthe first mentioned bushing, and means for releasably connecting thepulley to the second mentioned bushing.

16. In a mechanism of the class described, a shaft, a bushing on theshaft, a pulley mounted for rotation on said bushing and having a secondbushing interposed between the pulley and the first mentioned bushing,and a pin, adapted to be sheared by excess pressure, for connecting thepulley to the second mentioned bushing.

17. In a mechanism of the class described,

a shaft, a pulley, a clutch device for operatively connecting the pulleyto the shaft, starting means for initiating operation of the clutch andfor releasing the clutch from operative connection with the pulley,means for positively moving the clutch into engagement with the pulley,and means for positively operating. the starting means to clutchreleasing position.

18. In a mechanism of the class described, a shaft, a pulley, a clutchdevice for operatively connecting the pulley to the shaft, startingmeans comprising a member for initiating operation of the clutch and forreleasing the clutch from the pulley, means for causing engagement ofthe clutch with the pulley when the starting means initiates a clutchengaging operation, positively operated means for ensuring theengagement of clutch and pulley, and means for positively moving thesaid member to clutch releasing posit-ion.

19. In a mechanism of the class described, a shaft, a pulley, a clutchdevice for operatively connecting the pulley to the shaft, startingmeans comprising a member for initiating operation of the clutch and forreleasing the clutch from the pulley, a spring-operated member forcausing engagement of the clutch'with the pulley upon operation of thestarting means, a cam for ensuring positive actuation of the clutch, anda cam member automatically operative to move the starting member toclutch releasing position.

20. In a mechanism of the class described,

7 a shaft, a pulley, a clutch for operatively connecting the pulley tothe shaft, start ing means for controlling the operation of the clutch,a brake band normally operative to stop the shaft when the pulley hasbeen disconnected therefrom, manually operable and power operated meansoperating in succession to release the brake at the beginning ofrotation of the shaft, and means automatically operative for taking upthe slack in the brake band produced by the manually operated means andsubsequeptly applying the full force of the ra re.

21. In a mechanism of the character described, a shaft, a power pulley,clutching means operatively connecting the pulley to the shaft, a brakeoperative normally to prevent further rotation of the shaft after thedisconnection of the pulley from the shaft, and means comprising asegmental rack secured fixedly. to the shaft and a lock-co-opcratingtherewith for preventing rotation of the shaft in the reverse directionafter the unclutching of the pulley from the shaft.

2% In a mechanism of the character described, a shaft, a power pulley,clutching means operatively connecting the pulley to the shaft, a brakeoperative normally to prevent further rotation of the shaft after thedisconnection of the pulley from the shaft, segmental rack secured tothe shaft, a pawl for engagement with the rack to lock it and the, shaftagainst movement in the reverse direction, and a friction plateconnected to the pawl for moving it to operative and to inoperativepositions.

23. In a mechanism of the character de* scribed, a shaft, apower'pulley, a clutch for operatively connecting the pulley to theshaft, a brake for the shaft, means for releasing the brake prior to theclutching of the pulley to the shaft, means for further loosening thebrake as the shaft starts to rotate and for applying the brake at theproper time, and automatically operable means for conditioning the brakerelatively early in the cycle so that the full braking action of thebrake may be applied at the termination of the cycle at the instant thepulley is unclutched from the shaft.

24. In a mechanism of the character described, a shaft, a power pulley,a clutch for operatively connecting the pulley to the shaft, a brakeband for the shaft, means under the control of the operator forreleasing the brake band prior to the clutching of the pulley to theshaft, power operated means for further loosening the brake band as theshaft starts to rotate andfor apply ing the brake at the proper time,and positively operated means for taking up part of the slack in thebrake band relatively early in the cycle so that the full braking actionof the brake band may be applied at the termination of the cycle at theinstant the pulley is unclutched from the shaft.

25. Ina mechanism of the character described, a shaft, a pulley, aclutch for opera tively connecting the pulley to the shaft, a brake forthe shaft, manually operable means for releasing the brake prior to theclutching of the pulley to the shaft, power means for releasing thebrake, cam operated means fonrestoring the brake to the same extent thatit was released through the operation of said manually operable means,and means for applying the brake in full force at the instant the pulleyis. unclutched from the shaft.

26. In a mechanism ofthe character described, a shaft, a pulley, aclutch for operatively connecting the pulley to the shaft, a brake forthe shaft, manually operable means comprising a toggle arranged to bebroken for releasing the brake prior to the clutching of the pulley tothe shaft, power means, operable subsequently to the said manuallyoperable means, for releasing the brake, means operable subsequently tosaid.

power means for straightening the toggle for restoring the brake t0 thesame extent that it was released through the operation of said manuallyoperable. means, and means for applying the brake in full force at theinstant the pulley is unclutched from the shaft.

27. In a mechanism of the character described, ashaft, a pulley, aclutch, starting means comprising a positively controlled member forcontrolling the connection of the pulley to the shaft, a brake normallyoperative to stop the shaft when the pulley is unclutched therefrom, anda lock arranged to be returned positively to operative position by saidmember for preventing overthrow of the shaft beyond a predeterminedpoint.

28. In a mechanism of the character described, a shaft, a pulley, aclutch, starting means comprising a positively controller member forcontrolling the connection of the pulley to the shaft, a brake normallyoperative to stop the shaft when the pulley is unclutched therefrom, anda lock arranged to be returned positively to operative position by saidmember for preventing overthrow of the shaft beyond a predeterminedpoint, said starting means operating also to withdraw the lock fromoperative position so as to permit normal rotation of the shaft.

29. In a mechanism of the character described, a shaft, a pulley, aclutch, starting means comprising a positively controlled member, foroperatively connecting the pulley to and disconnecting it from theshaft, a brake normally operative to stop the shaft when the pulley isunclutched therefrom, a lock arranged to be returned positively tooperative position by said member for preventing overthrow of the shaftbeyond a predetermined point, and spring means also operative to movethe lock to operative position.

30. In a mechanism of the character described, a shaft, a pulley, aclutch, starting means comprising a positively controlled member foroperatively connecting the pulley to and disconnecting it from theshaft, a brake normally operative to stop the shaft when the pulley isunclutched therefrom, and a finger arranged to be positively returned tooperative position by said member for locking the starting means againstoperation.

31. In a mechanism of the character described, a shaft, a pulley, aclutch for operatively connecting the pulley to the shaft comprising asplit ring, and means for operating the ring to engage and to releasesaid pulley comprising a toggle between the ends of the splitring, aspring-operated member for straightening the toggle to apply the ring tothe pulley, and a cam for ensuring the straightening of the toggle.

32. In a mechanism of the character described, a shaft, a pulley, aclutch starting means comprising a positively controlled member foroperatively connecting the pulley to and disconnecting it from theshaft,

a brake normally operative to stop the shaft when the pulley isunolutched therefrom, and connections between the positively controlledmember and the brake for operating the latter in properly timed relationto the disconnection of the clutch.

33. In a mechanism of the class described, a shaft, a bushing on theshaft, a power pul ley rotatable on the bushing, a clutch foroperatively connectinpthe pulley to the shaft, starting means forcontrolling the operation of the clutch, and means for locking thestarting means against manual operation in case the pulley should seizethe bushing and carry it to a predetermined position.

34-. In a mechanism of the class described, a shaft, a bushingreleasably attached to the shaft to move therewith under normalconditions, a pulley mounted for rotation on the bushing, a clutch foroperatively connecting the pulley to the shaft, starting means forcontrolling the operation of the clutch, and means for locking thestarting means against operation in case the pulley seizes upon andmoves the said bushing relatively to the shaft.

85. In a mechanism of the class described,

a shaft, a bushing on the shaft, means for releasably connecting thebushing to the shaft, a power pulley rotatable on the bushing, a clutchfor operatively connecting the pulley tothe shaft, starting means forcontrolling the operation of the clutch, and means carried by thebushing for locking the starting means against manual operation in casethe pulley should seize the bushing and carry it along to apredetermined position.

36. In a mechanism of the class described, a shaft, a bushing on theshaft, means for releasably connecting the bushing to the shaft, a powerpulley rotatable on the bush ing, a clutch for operatively connectingthe pulley to the shaft, starting means for controlling the operation ofthe clutch, and a hook carried by the bushing for locking the startingmeans against manual operation in casethe pulley carries the bushingalong with it due to friction between the pulley and bushing.

37. In a mechanism of the class described,

a shaft, a bushing on the shaft, a spring pressed plunger for releasablyattaching the bushing tov the shaft, a hook fixedly carried by thebushing, a power pulley rotatable on the bushing, a clutch foroperatively connecting the pulley to the shaft, starting means forcontrolling the operation of the clutch, and a member associated withthe starting means and located in the path of movement of the hook onthe bushing, the construction and arrangement being such that movementof the bushing to a predetermined extent relatively to the shaft willcause engagement of the hook with the start- 1 means for releasablyconnecting the second bushing to the power pulley, a clutch foroperatively connecting the pulley to the shaft, starting means forcontrolling the operation of the clutch, and a member associated withthe starting means and located in the path of movement of the hook onthe bushing, the construction and arrangement being such that movementof the first mentioned bushing to a predetermined extent relatively tothe shaft will cause engagement of the hook with the starting member,thereby preventing operation of the starting means by the operator andpreventing also further rotation of the first-mentioned bushingwhereupon the connection between the pulley and the second-mentionedbushing may be broken to permit the pulley to turn on the latterbushing.

39. In a mechanism of the character described, a shaft, a power pulley,clutch mechanism for operatively connecting the pulley to the shaft,startingmeans for controlling.

the clutch, and means for preventing efiective operation of the startingmeans in case the shaft overthrows to a predetermined extent.

40. In a mechanism of the character described, a shaft, a power pulley,clutch mech anism for operatively connecting the pulley to the shaft, abrake operative normally to stop the rotation of the shaft afterdisconnection of the clutch, starting means for controlling the clutch,and means for preventing effective action of the starting means in casethe shaft overthrows to a predetermined extent due to improper operationof the brake or clutch or both of these elements.

41. In a mechanism of the class described, a shaft, a power pulleyloosely mounted on the shaft, clutch means for operatively connectingthe pulley to the shaft comprising a member keyed to the shaft andhaving a shoulder, a brake operative normally to prevent furtherrotation of the shaft after the disconnection of the pulley from theshaft, a locking pawl for co-operation with the shoulder on said keyedmember for locking the shaft against excess rotation should the brakebecome inoperative, and means for positively returning the locking pawlto operative position before the end of the rotative movement of theshaft.

42. Ina mechanism of the character described, a shaft, a pulley looselymounted on the shaft, a clutch for operatively connecting the pulley tothe shaft comprising a split ring, means for operating the ring to ing atoggle between the ends of the split ring, a spring operated member forstraightening the toggle to apply the ring to the pulley, and positivelyoperated means for insuring the straightening of the toggle.

as. In a mechanism of the character described, a shaft, a pulley looselymounted on the shaft, a clutch for operatively connecting the pulley tothe shaft comprising a split ring, means for operating the ring toengage and to release said pulley comprising a toggle between the endsof the split ring, a spring operated member for straightening the toggleto apply the ring to the pulley, and a cam arranged to operate upon saitmember to insurethe straightening of the toggle'alld the m engagement ofthe split a:

ring with the friction surface on the pulley.

4A. In a mechanism of the character described, a shaft, a power pulleyloosely mounted on the shaft, a clutch for opera-, tively connecting thepulley to the shaft, a brake for the shaft, means for releasing thebrake prior to the clutching of the pulley to the shaft, means forfurther loosening the brake as the shaft starts to rotate and forapplying the brake at the proper time, and

means operable independently of the clutch for conditioning the brakerelatively early in the cycle of operations so that the full brakingaction of the brake may be applied at the termination of the cycle atthe instant the pulley is unclutched from the shaft.

In testimony whereof I have signed my name to this specification.

MILTON H. BALLARD.

engage and to release said pulley compris-' CER'HMGATE 0F GQRREGTWNBPatent No. 1,620,061. Granted March 8, 1927, to

MEL'EQN H. BALLARDG It i8 hereby sort-fitted that error appeam in theprinted sptcitieation of the above tmmbered patent tequirittg'oorrootton ttt! follows: Page it, line 22, for the "word "beams" road"beam", and time 41, for the Wort. "part" toad "parts"; page 5, tins 31for the Word. "hightsr" read "high"; page 11, lines 49 and 50, claim 41,lines 64; and =65, claim t2, and lines 75 and 76, claim 45, strike outthe words "loosoly mounted on the shaft"; and that the said LettersPatent should be read with these cOfi'fitfitltimlS thtrein that the samemay conform to the record of the case in the Patont fifties.

Signed and seated this 4th day of Uctober, A. D. 1927.

M. J. Moore, Seal. Acting @ommiosioner of Patents.

